Reference is made to FIG. 1, which shows a fluorescence microscopic imaging apparatus according to the conventional technology. The fluorescence microscopic imaging apparatus includes: a fluorescence excitation light source 1, a dichroic mirror 2 arranged to form an angle of 45 degrees with an irradiation direction of the monochromatic fluorescence excitation light source 1, an objective lens 3, a sample placing platform 4, an emitting light filter 5 and a camera 6. The monochromatic fluorescence excitation light source 1 emits excitation light, and the excitation light is reflected to the objective lens 3 through the dichroic mirror 2, and then irradiates to a to-be-detected sample plate on the sample placing platform 4. Particles within the to-be-detected sample plate emit fluorescence due to excitation, and the fluorescence enters the camera 6 to generate an image after passing through the dichroic mirror 2 and the emitting light filter 5. The conventional fluorescence microscopic imaging apparatus needs to separate light using the dichroic mirror, and thereby resulting in that the fluorescence microscopic imaging apparatus has a complicated structure and a high cost.